While preparing for tonight’s A’s-Red Sox series opener, Cespedes is also preparing for Monday’s Home Run Derby in New York.

He crushed a lot of pitches from third-base coach Mike Gallego, who’ll pitch to him in the derby, some reaching destinations that are out of reach for other ballplayers.

There’s a history of hitters slumping in the second half because they messed up their stroke in the derby. Bob Melvin was asked if it might have an opposite effect for Cespedes, who’s hitting .221.

“I wouldn’t argue that,” Melvin said. “He’s a spotlight type guy, as we’ve seen since he first got here. I know he’s excited about it and rightly so. It gives us a little bit more exposure because it’s a heavily watched event. If there was ever a guy who’s right for it, it’s him.

“I think as much as anything, you worry about injury. But anybody who’s in it, the further you go along in it, it does take it toll physically because you’re taking a lot of swings and you’re swinging pretty hard. It’ll be good for him to be in that spotlight. He likes the spotlight.”

The A’s would love for Cespedes to put on a show for the national audience. More important is that he comes away healthy.

“I don’t think he’ll be doing it with a donut on the back,” said a smiling Melvin, recalling that a weighted donut hasn’t prevented Cespedes from reaching the fences. “That’s one thing we’ve got him to cut down on some.”

—– Bartolo Colon hasn’t publicly said whether he’ll make himself eligible for Tuesday’s All-Star Game. He has a choice to opt out because he’s starting Sunday. If he removes himself from the roster, with which the A’s would be OK, Grant Balfour would be the likely choice for AL manager Jim Leyland.

Balfour can’t be snubbed again.

Can he?

Asked for a Colon update, Melvin said, “It should come from him. Not me.” With a chuckle, Colon said of his All-Star status, “I don’t know.”

Either way, Balfour should be an All-Star already.

Can’t be more perfect as a closer than 24-for-24.

—– Infielder Adam Rosales is heading back to Triple-A Sacramento after being outrighted by the A’s. He had been designated for assignment and cleared waivers, and Melvin’s happy he’s back in the organization, though he would have been in the big leagues if claimed by another team.

“Obviously, you’d like him to be in the big leagues somewhere,” Melvin said. “Even when I had talked to him, he was excited about it either way because he does love the organization. He wants to be here.

“I think he’s excited about getting to play some and stay in the organization. Not as much as I am. We’re all excited about him still being an A.”

—– The next appearance for prized prospect Sonny Gray? “We’re certainly not opposed to using him in an important situation. . . . Very impressive kid, and we’d use him in any particular role,” Melvin said.